Main Entry: Laugh·ter·bate
Pronunciation: "Lauf-t&r-'bA-te
Function: noun
: comic stimulation especially of one's own sense of humor commonly resulting in laughing till you shit your own pants and achieved by written or other forms of amusement such as photo's or drawing concocted solely for the purpose of self entertainment,or by various combinations of these agencies

"johnny's sudden and unexpected episode of laughterbation in public was shocking!.. but slightly amusing, though the purpose of his antics where for his own selfish desire for a cheap laugh"